Microchip Technology RE46C141S16TF

Overview

RE46C141S16TF from R&E International (a Microchip Technology subsidiary) is a CMOS photoelectric smoke detector ASIC with integrated interconnect functionality, low-power strobed detection (4 µA standby current at 9 V), temporal horn pattern compliance with NFPA 72, and UL 217/UL 268 recognition. It integrates gain-selectable photoamplifier, internal oscillator, IRED driver, dual-tone horn control (HB/HS), and bidirectional interconnect logic for up to 40-unit networks - deployed in residential and commercial hardwired smoke alarms.

For engineers reviewing the RE46C141S16TF datasheet, RE46C141S16TF pinout, RE46C141S16TF application, or RE46C141S16TF equivalent, key selection considerations include its 16-pin SOIC-W package, 8.1 s nominal strobe period, VDD=6–12 V operation, interconnect timing delay (0.9–1.65 s), and chamber integrity test capability every 32 seconds.

Technical Context

The RE46C141S16TF implements a pulsed photoelectric detection architecture: an internal oscillator enables 100 µs IRED pulses every 8.1 s in standby, increasing frequency upon smoke detection. Its dual-gain photoamplifier (C1 for high-gain test, C2 for normal sensitivity) interfaces with external photodiode and IR emitter via DETECT and IRED pins.

It features a bidirectional IO pin with 500 ms digital filtering, constant-current drive during local alarm, and 1 s charge-dump discharge post-alarm. Horn outputs (HB/HS) deliver complementary piezoelectric drive for temporal pattern generation (500 ms on / 1.5 s off), while LBSET and TEST pins configure low-battery threshold and push-button chamber testing.

Key Specifications

Pinout & Package

RE46C141S16TF is housed in a 16-lead Wide SOIC (SOIC-W) package with 1.27 mm pitch, RoHS-compliant, surface-mount footprint.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar photoelectric smoke detector ASIC applications.

Compared with MC145012P, RE46C141S16TF integrates interconnect, temporal horn, and low-power strobing - reducing system-level component count by ≥5 discrete parts. Versus RE46C142S16F, it provides identical functionality in a thermally superior wide-body package optimized for sustained horn drive duty cycles.

Availability

RE46C141S16TF is available at Aetrix Electronics and suitable for residential fire safety systems, commercial building alarm networks, and battery-backed smoke detector modules requiring stable component supply, long-lifecycle assurance, and UL-certified design reuse.

Supply support for RE46C141S16TF includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

R&E International is a wholly owned subsidiary of Microchip Technology Inc., specializing in highly integrated, safety-critical analog/mixed-signal ICs for fire and life safety applications.

The RE46C141S16TF belongs to R&E's photoelectric smoke detector ASIC product line, engineered specifically to replace discrete detector designs with single-chip solutions meeting UL 217/268 and NFPA 72 requirements.

FAQ

What is the operating voltage range for the RE46C141S16TF?

The RE46C141S16TF operates from 6 V to 12 V DC, supporting both alkaline and carbon-zinc battery chemistries commonly used in smoke detectors. Its internal regulation and low-quiescent-current design maintain stable performance across this full range without external LDOs or voltage dividers.

How does the RE46C141S16TF implement interconnect functionality?

The RE46C141S16TF uses its bidirectional IO pin to support wired interconnection of up to 40 detectors. During local alarm, it drives IO high via constant-current source; when configured as input, it detects remote alarms through a 500 ms digital filter - enabling reliable multi-unit signaling without external transceivers or protocol stacks.

Does the RE46C141S16TF support NFPA 72 temporal horn patterns?

Yes, the RE46C141S16TF natively generates the NFPA 72 Class 2 temporal pattern (500 ms ON / 1.5 s OFF) using its complementary HB and HS outputs. This eliminates the need for external timing components or microcontroller firmware to meet emergency evacuation signal requirements.

What is the purpose of the C1 and C2 pins on the RE46C141S16TF?

C1 sets high-gain photoamplifier response (A = 1 + C1/10 pF) for push-button chamber testing and background reflection checks; C2 sets normal-gain response (A = 1 + C2/10 pF) for standby smoke detection. Their independent configuration allows precise sensitivity tuning and reliable functional verification.

Is the RE46C141S16TF UL recognized, and for which standards?

Yes, the RE46C141S16TF is UL Recognized under File S24036 for compliance with UL 217 (Standard for Single and Multiple Station Smoke Alarms) and UL 268 (Standard for Smoke Detectors). This recognition covers its use in photoelectric-type smoke detection circuits meeting North American safety requirements.